Asymmetrical-wound toroid yoke cathode ray tube deflection system

ABSTRACT

A color cathode ray tube deflection system includes a color cathode ray tube having triad-arrayed electron guns, a toroid deflection yoke having deflection windings symmetrical to the vertical axis and asymmetrical to the horizontal axis of a core of magnetic material, and dynamic convergence means for effecting radial movement of electron beams from said electron guns whereby horizontal and vertical trace lines on a viewing screen of the cathode ray tube are converged.

United States Patent Torsch 14 1 June 20, 1972 ASYMMETRICAL-WOUND TOROID 3,430,099 2/1969 Ashley ..335/213 ux YOKE- CATHODE RAY TUBE 3,548,350 2/1970 Archer ..335/210 DEFLECTION SYSTEM FOREIGN PATENTs 0R APPLICATIONS [721 Imam" Edward Tmdh Geneva, 514,170 1 1/1939 Great Britain .335/210 [73] Assignee: GTE Sylvania Incorporated Primary Examiner-George Hams Flledi y 1971 Attorney-Norman J. OMalley, et al. [21] Appl. No.: 160,865 ABSTRACT A color cathode ray tube deflection system includes a color (5|. "3351213612: cathode y tuba having triad a"ayed electron guns. 8 tomid 58] a 1 3/75 deflection yoke having deflection windings symmetrical to the /27 vertical axis and asymmetrical to the horizontal axis of a core of magnetic material, and dynamic convergence means for effecting radial movement of electron beams from said electron [56] Rdennces Cited guns whereby horizontal and vertical trace lines on a viewing UNITED STATES PATENTS screen of the cathode ray tube are converged.

2,925,542 2/1960 Gethmann ..335/2l3 15 Claims, 6 Drawing Figures PATENTEDJUHZO I972 SHEET 10$ 4 IN VENTOR. CHARLES E. TORSCH BY 8' L ATTORNEY Pmmemunzo 1972 3.671.897

sum 2 0F 4 INVENTOR. 2 l 15' CHARLES E. TORSCH JM 1 M ATTORNEY PATENTEnJuuzo I972 3.671.897

SHEET 30F 4 If I 70 4| {J43 so HORIZONTAL TURNS (AccuMuLAT|vE)-- IN VEN TOR.

CHARLES E. TORSCH Y 1 M i- ATTORNEY VERTICAL TURNS (AccuMuLAT|vE) 70 P'A'TENTEDJmo I972 3 ,8 97

smasr u or 4 IO 4o so ANGLES FROM VERTICAL. AXIS ASYMMETRICAL-WOUND TOROID YOKE CATHODE RAY TUBE DEFLECTION SYSTEM BACKGROUND OF THE INVENTION In the field of cathode ray tube deflection systems, there are two rather broad and well-known cathode ray tube categories i.e., triad and in-line. The triad system, which is most common, utilizes a color cathode ray tube having red, green, and blue electron guns arrayed in the form of a triad with a viewing screen whereon red, green, and blue phosphor deposits are arrayed in a triad. Electron beams from the electron gun are directed toward and impinge the phosphor dots on the viewing screen. Also, a deflection yoke and electromagnet means are normally employed to effect development of dynamically converged red, green, and blue traces on the viewing screen.

The other category of deflection system is the in-line type wherein a color cathode ray tube includes red, green, and blue electron guns arrayed along a horizontal axis. A deflection yoke affixed to the cathode ray tube effects deflection of the electron beams from the in-line guns to provide a plurality of multi-sized rasters. These multiple rasters are altered in size by a size control which is also affixed to the in-line color cathode ray tube.

Further, deflection yokes for the above-described triad and in-line cathode ray tube systems are of two well-known categories e saddle and toroid. The saddle yoke normally em-, ploys a cosine distribution and manufacture often includes coating wire with a thermosetting plastic and pressing into a desired shape. Moreover, saddle yokes are undesirably heavy, due to the large amount of wire, undesirably expensive, and leavesomething to be desired in uniformity and repeatability of obtainable results.

The toroid-type deflection yoke utilizes a core member of relatively high permeability with horizontal and vertical deflection windings wrapped thereon. The yoke is relatively light, inexpensive, and provides a highly desirable uniformity and repeatability of results.

As to deflection systems, one form of deflection system is suggested in U.S. Pat. No. 3,430,099 issued to R. B. Ashley and U.S. Pat. No. 3,548,350 issued to J. R. Archer. Therein, the deflection system includes a color cathode ray tube wherein the electron guns are arrayed in a line, a toroid deflection yoke of a design compatible with the in-line color cathode ray tube, and a size control for altering the dimensions of a plurality of different sized rasters. Obviously, a deflection system adapted to an in-line color cathode ray tube is not particularly suitable to deflection systems employing a triad arrayed color cathode ray tube.

Also, a deflection system employing a triad color cathode ray tube and a toroid deflection yoke is disclosed in U.S. application, Ser. No. 145,884 which is a continuation application of Ser. No. 841,893 (now abandoned) filed July 14, 1969 in the name of Charles Edward Torsch, the present applicant, and entitled Deflection System for Triad Beam Cathode Ray Tubes. Therein, a deflection system for a triad color cathode ray tube utilizes a toroid deflection yoke to effect the appearance on a viewing screen of two horizontal trace lines having substantially identical arcs.

Although the above-mentioned in-line color cathode ray tube systems employing toroid yokes are of interest, it is obvious that such systems and techniques are inappropriate to a triad arrayed color cathode ray tube deflection system. Also, the above-listed triad system is of interest insofar as convergence of horizontal trace lines is concerned. However, it can be readily understood that convergence of both horizontal and vertical trace lines with a minimum of convergence apparatus and circuitry is a highly desirable condition.

OBJECTS AND SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide an enhanced cathode ray tube deflection system. Another object of the invention is to provide an improved deflection system employing a triad-arrayed color cathode ray tube. Still another object of the invention is to initiate an improved deflection system which includes a color cathode ray tube with electron guns arrayed in a triad and a toroid wound deflection yoke. A further object of the invention is to provide an improved deflection system for effecting convergence of both horizontal and vertical trace lines on a viewing screen of a triad-arrayed color cathode ray tube.

These and other objects, advantages and capabilities are achieved in one aspect of the invention by a deflection system employing a color cathode ray tube having triad-arrayed electron guns, a toroid deflection yoke associated with the cathode ray tube, and radial convergence apparatus for effecting dynamic convergence of both horizontal and vertical trace lines on a viewing screen.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top prospective illustration of a color cathode ray tube deflection system utilizing a triad-arrayed cathode ray tube, toroid deflection yoke, and convergence means;

FIG. 2 is a diagrammatic illustration of a toroid deflection yoke applicable to the deflection system of FIG. 1;

FIGS. 3 and 4 are graphical illustrations of the horizontal and vertical winding distribution of the toroid yoke of FIG. 2;

FIG. 5 is a graphic illustration of horizontal and vertical trace lines observable on the viewing screen of the cathode ray tube of FIG. 1; and

FIG. 6 is a diagrammatic illustration of a convergence means suitable for use with the color cathode ray tube of FIG. 1.

DESCRIPTION OF A PREFERRED EMBODIMENT For a better understanding of the present invention, together with other and further objects, advantages and capabilities there of, reference is made to the following disclosure and claims in conjunction with the accompanying drawings.

Referring to the drawings, FIG. 1 indicates a color cathode ray tube 9 having three electron guns ll, 13, and 15 arrayed in a triad configuration. The electron guns ll, 13, and 15 provide electron beams 17, 19, and 21 which impinge triad-arrayed red, green, and blue phosphors on a viewing screen 23 to provide red, green, and blue traces.

A toroid deflection yoke 25, which will be more fully detailed, is associated with the CRT 9 and serves to effect both horizontal and vertical deflection of the electron beams l7, l9, and 21. Also, convergence means in the form of static and dynamic convergence apparatus 27 and a blue lateral magnet means 29 are associated with the CRT 9 and cooperate with the deflection yoke 25 to effect a desired convergence of the electron beams 17, 19, and 21 and provide substantially coincident static and dynamic red, green, and blue horizontal and vertical traces on the viewing screen 23.

The toroid deflection yoke 25, as illustrated in FIG. 2, includes a core member 31 of a relatively high permeability material with a horizontal axis H-l-l and a vertical axis V-V'. First and second vertical deflection windings 33 and 35, respectively, having substantially the same number of turns wrapped on the core member 31 and indicated by blackened dots, are disposed upon opposite sides of the horizontal axis H-JI. First and second horizontal deflection windings 37 and 39, respectively, having substantially the same number of turns wrapped about the core member 31 and indicated by white dots, are disposed on opposite sides of the vertical axis V-V'.

The deflection yoke 25 is formed for association with the CRT 9 such that the blue electron gun 15 of the CRT 9 is above the horizontal axis H41 and the red and green electron guns 1! and 13 are below the horizontal axis l-H-l'. Also, the first vertical deflection winding 33 is located above the horizontal axis H-Ji' while the second vertical deflection winding 35 is below the horizontal axis I-I-I-l'.

Further, the first and second vertical deflection windings 33 and 35 are asymmetrical with respect to one another about the horizontal axis l-I-I-I' and each of the windings 33 and 35 is symmetrical with respect to the vertical axis V-V'. The first and second horizontal deflection windings 37 and 39 are each asymmetrical with respect to the horizontal axis H-H' and symmetrical to one another about the vertical axis V-V'. Obviously, reversal of the CRT 9 would necessitate reversal of the deflection yoke 25. In other words, rotation of the CRT 9 by 180 would be accompanied by a 180 rotation of the yoke 25.

Additionally, the accumulative turns of the horizontal deflection windings are graphically illustrated in FIG. 3. Therein, a curve 41! illustrates the accumulative turns in percent of that portion of one of the horizontal deflection windings 37 and 39 at an angle above the horizontal axis I'I-H'. A second curve 43 graphically illustrates the accumulative turns in percent of one of the horizontal deflection windings 37 and 39 at any given angle 0 below the horizontal axis. Moreover, it has been found that variations of 0 within about 3 provide satisfactory results.

Similarly, FIG. 4 graphically illustrates a comparison of the asymmetrical first and second vertical deflection windings 33 and 35. The curve 45 illustrates the winding distribution or accumulative turns in percent of the first vertical deflection winding 33 at an angle 4) from the vertical axis V-V' and above the horizontal axis I-I-H. Curve 47 illustrates the accumulative turns in percent of the second vertical deflection winding 35 at an angle d from the vertical axis V-V' and below the horizontal axis I-I-I'I'. Again, variations of d; within about 3 have been found to provide satisfactory results.

Observation of the horizontal deflection windings, 37 and 39, as represented by the curves 41 and 43, illustrates that at least 70 percent of the accumulative turns are included within an angle 0 of about 45 from the horizontal axis I-I-I-I'. Also, at least 70 percent of the accumulative turns of the vertical deflection windings 33 and 35 are included within an angle (3" of about 45 from the vertical axis V-V' The horizontal deflection windings above the horizontal axis H-I-I are represented by the following formulation:

Ha =2.0246 2.0161 0 0.0076495 0 0.000064226 0 0.00000108l9 0" wherein 6 is the angular deviation from the horizontal axis I-I-l-I' and variable within about 3.

The horizontal deflection windings below the horizontal axis I-I-I-I', which are asymmetrical to the above-mentioned horizontal windings above the horizontal axis Ha, are represented by the following formulation:

Hb 0.77343 1.69224 6 0.0022040 0 -0.0000636l4 0 0.00000l08l9 0" wherein 6" is the angular deviation from the horizontal axis I-IJ-l and variable within about 3".

Similarly, the first vertical deflection winding 33 above the horizontal axis l-i-I-I' is represented by the following formulation:

Va 0.52324 1.0379 0.071690 ti -0.001733l qb 0.000011160 5 wherein it is the angular deviation from the vertical axis V-V' and variable within about 3.

The second vertical deflection winding 35 below the horizontal axis I-I-I-I' and asymmetrical to the above-mentioned first vertical deflection winding 33 is represented by the following formulation:

Bv 0.77343 1.6922 0.0022040 4a 0.0000636l4 e5 -0.00000044608 4) wherein the angle qT is the angular deviation from the vertical axis V-vV' and variable within about 3.

As can be determined by the above-mentioned formulation and observed in FIG. 2, the turns of the second vertical winding 35 are more concentrated at the center thereof than the turns of the first vertical winding 33. However, the turns of the first vertical winding 33 are more concentrated to the left and right of center than the turns of the second vertical winding 35. Thus, magnetic field compensation for the off-axis blue electron gun is provided.

Also, the horizontal deflection windings 37 and 39 have been wound to provide a somewhat weakened magnetic field at the horizontal axis I-I-I'l' such that red (R) and green (G) vertical trace lines are substantially centered about the blue (8) vertical trace line. Moreover, each of the first and second horizontal deflection windings 37 and 39 includes an increased concentration of windings above the horizontal axis I-i-I-I' to I provide magnetic field compensation for the mechanical displacement of the red and green electron guns. Thus, uniformity of the red and green traces above and below the horizontal axis l-l-I-I' is achieved.

As can readily be seen in the illustration of FIG. 5, the above-mentioned deflection yoke 25 and CRT 9 having triadarrayed red, green, and blue electron guns 1 1, l3, and 15 provide trace lines upon application of sawtooth potentials common to color TV receivers. The horizontal red (R) and green (G) trace lines are of substantially similar slopes and tend to have substantially similar arcs while the horizontal blue (B) trace line tends to deviate therefrom whereupon correction of the blue (B) trace is required.

The vertical trace lines are represented by red (R) and green (G) trace lines forming substantially similar but oppositely directed arcs. These red (R) and green (G) trace lines are also disposed on opposite sides of the blue (B) trace line. Moreover, the above-mentioned condition is appropriate to but reversed for opposite sides of the viewing screen due to the horizontal alignment and positioning of the red and green electron guns. In other words, the red (R) trace line is external to the blue (B) trace line on one side of the viewing screen but internal thereto on the other side of the viewing screen. A similar condition also exists for the green (G) trace lines.

In order to provide the desired convergence of both horizontal and vertical trace lines, a convergence means in the form of static and dynamic convergence apparatus, 27 of FIG. 1, and blue lateral magnet means 29 are employed. Such apparatus is well known in the color TV art and presently utilized in systems with triad-arrayed cathode ray tubes and socalled saddle-type deflection yokes.

Briefly, FIG. 6 illustrates a preferred form of convergence means wherein a permanent magnet 49 is affixed to an electromagnet 51 positioned adjacent each one of the red (R), green (G), and blue (8) electron guns. The permanent magnets 49in conjunction with the blue lateral magnet, 29 of FIG. 1, serve to efiect static convergence at the center of the viewing screen 23. The electronmagnets 51 serve to effect dynamic radial alteration of the electron beams emanating from the electron guns (R, G, and B) as indicated by the arrows.

Thus, the toroid deflection yoke 25 employed with a color cathode ray tube 9 with triad-arrayed red, green, and blue electron guns 11, 13, and 15 serve to provide both horizontal and vertical deflection of the electron beams. This deflection is of a design such that red (R) and green (G) horizontal traces have substantially similar arcs while the red (R) and green (G) vertical traces have similar but oppositely directed arcs. Moreover, the horizontal blue (B) trace deviates from the horizontal red (R) and green (G) traces while the vertical blue (B) trace is disposed intermediate the vertical red (R) and green (G) traces. A convergence means, well known in the color TV art, is utilized to effect the desired convergence of the above-mentioned trace lines in both horizontal and vertical directions.

As a result, there has been provided a unique color cathode ray tube deflection system which includes a triad-arrayed color cathode ray tube, a toroid deflection yoke, and a convergence means. The non-symmetry of the triad-arrayed CRT in conjunction with the asymmetrical toroid yoke provides a desired trace line convergence at a minimum of cost as compared with other known systems. Also, the toroid yoke tends to provide a desired reduction in component weight, cost and size which enhances the uniformity and repeatability of the desired result.

While there has been shown and described what is at present considered the preferred embodiment of the present invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention as defined by the appended claims.

I claim:

l. A color cathode ray tube deflection system comprising:

a color cathode ray tube having triad-arrayed red, green, and blue electron guns each emanating an electron beam for effecting red, green, and blue horizontal and vertical traces on a viewing screen;

a toroid deflection yoke associated with said color cathode ray tube and including a core of magnetic material having horizontal and vertical axes with horizontal and vertical deflection windings wrapped about said core and substantially asymmetrical about said horizontal axis and symmetrical about said vertical axis; and

dynamic convergence means associated with said color cathode ray tube for efiecting electron beam radial movement and in combination with said toroid deflection yoke effecting convergence of both horizontal and vertical red, green, and blue traces on said viewing screen.

2. The deflection system of claim 1 wherein said deflection yoke includes first and second horizontal deflection windings disposed on opposite sides of said vertical axis wherein each have substantially the same number of turns.

3. The deflection system of claim 1 wherein said deflection yoke includes first and second vertical deflection windings disposed on opposite sides of said horizontal axis with each having substantially the same number of turns. a

4. The deflection system of claim 1 wherein said blue electron gun of said color cathode ray tube is disposed above and said red and green electron guns are disposed below the horizontal axis of said core of said deflection yoke and said vertical deflection windings are formed to provide a lower concentration of windings at the top central portion as compared with the winding concentration at the bottom central portion of said deflection yoke.

5. The deflection system of claim 1 wherein said blue electron gun of said color cathode ray tube is disposed above and said red and green electron guns are disposed below the horizontal axis of said core of said deflection yoke and said first and second horizontal deflection windings have a greater concentration of turns above and adjacent the horizontal axis l-l-l-l than below and adjacent the horizontal axis H-l-l.

6. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said horizontal deflection windings have a portion above the horizontal axis defined by a formula substantially as follows:

Ha 2.0246 2.0161 9 0.0076495 0 +0.000064226'l9 0.00000l08l9 0 wherein 0 is the angular deviation from the horizontal axis l-l-H' within 3'. V

7. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said horizontal deflection windings have a portion below said horizontal axis defined by a formula substantially as follows:

Hb 0.77343 1.69224 6 +0.0022040 0* -0.000063614 0 -0.0000010819 0 wherein 0 is the angular deviation from the horizontal axis H-l-l' within about 3.

8. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said vertical deflection windings include a first vertical deflection winding disposed above said horizontal axis with substantially similar portions on opposite sides of said vertical axis and each portion is defined by a formula substantially as follows:

Va 0.52324 1.0379 0.071690 it 0.00l733l d 0.0000l l 160 4:

wherein 1b is the angular deviation from the vertical axis V-V' within about 3.

9. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said vertical deflection windings include a second vertical deflection winding disposed below said horizontal axis with substantially similar portions on opposite sides of said vertical axis and each portion is defined by a formula substantially as follows:

Vb 0.77343 1.6922 at 0.0022040 rb' -0.000063614 4i 0.00000044608 it wherein (b is the angular deviation from the vertical axis V-V' within about 3.

10. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said vertical deflection windings include a first vertical deflection winding disposed above said horizontal axis with substantially identical portions on opposite sides of said vertical axis and at least percent of the total turns of one portion within a counter-clockwise angle of 45 as measured from the vertical axis.

1 1. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said vertical deflection windings include a second vertical deflection winding disposed below said horizontal axis with substantially identical portions on opposite sides of said vertical axis and at least 70 percent of the total turns of one portion within a counterclockwise angle of about 45' as measured from the vertical axis.

12. In a color television receiver, a deflection system comprising:

color cathode ray tube means providing red, green, and blue horizontal and vertical traces on a viewing screen, said traces derived from electron beams emanating from triadarrayed red, green, and blue electron guns;

toroid deflection yoke means associated with said color cathode ray tube means for effecting horizontal and vertical deflection of said electron beams, said yoke means including a core of magnetic material having horizontal and vertical axes, first and second horizontal deflection windings wrapped about said core on opposite sides of said vertical axis with each winding asymmetrical to said horizontal axis and first and second vertical deflection windings wrapped about said core on opposite sides of said horizontal axis with each of said windings substantially symmetrical to said vertical axis and asymmetrical to said horizontal axis;

static convergence means associated with said color cathode ray tube for effecting convergence of said electron beams at the center of said viewing screen, said means including red, green, and blue radial magnets and a blue lateral magnet; and

dynamic convergence means associated with said color cathode ray tube for effecting radial movement of said electron beams during deflection thereof by said yoke means to provide converged horizontal and vertical red, green, and blue traces, said means including an electromagnet for effecting radial movement of each of said red, green, and blue electron beams.

13. The deflection system of claim 12 wherein said color cathode ray tube includes a blue electron gun above and red and green electron guns below said horizontal axis of said core and said deflection yoke means provides a lower concentration of vertical windings at the center portion above said horizontal axis as compared with the concentration of windings at the center portion below said horizontal axis whereby convergence of horizontal and vertical red, green, and blue traces is effected.

14. The deflection system of claim 12 wherein said blue electron gun is disposed above and said red and green electron guns are disposed below said horizontal axis of said core and said first vertical deflection winding disposed above said horizontal axis includes substantially similar winding turns on opposite sides of said vertical axis with at least 70 percent of the total turns of one of said winding portions included within an angle of 45 as measured counter-clockwise of said vertical 3 53 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent 'No. 3 3 Dated 7 June 20, 1972 Inventor( s) Charles Edward Torsch 'It is certified that error appears in the above-iidentified patent and that-said Letters Patent are hereby corrected as s hown below:

Col. 1, line 10 delete "gun" and insert guns Col. 4, line 46 delete "electronmagnets" and insert electromagnets Col. 5, (31 im 8; line 74-delete "Va'= 45.52324 1.0379 0.071690 d and insert Va 0.52324 1.0379 05 0.071690 d Signed and sealed thisBth day ofDecember 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GUTTSCHALK Attesting Officer Commissioner of Patents mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N0. I Dated June 20,

Inventor-(s) Charles Edward Torsch It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col'. 1, line 10 delete "gun" and insert guns Col. 4, line 46 delete "electronmagnets" and ir lsert electromagnets Col. 5, cl im 8, line 74-delete "Va #052324 1.0379 0.071690 (6 and insert Va -0.52324 1.0379 05 0.071690 d Signed and sealed this-5th day ofDecember 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,J'R, ROBERT GUT'I'SCHALK Attesting Officer Commissioner of Patents 7 3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,671,897 Dated June 20, 1972 Inventor( s) Charles Edward Torsch It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 1, line 10 delete "gun" and insert guns Col. 4, line 46 delete "electronmagnets" and insert electromagnets Col. 5, (:1 im 8, line 74-delete "Va -0.52324 1.0379

0.071690 6 and insert Va -0.52324 1.0379 (25 0.071690 (25 Signed and sealed this 5th day of December 1972.

(SEAL) Attest: v

EDWARD M.FL11;TCHER,JR, ROBERT GUT'I'SCHALK Attesting Officer v Commissioner of Patents 

1. A color cathode ray tube deflection system comprising: a color cathode ray tube having triad-arrayed red, green, and blue electron guns each emanating an electron beam for effecting red, green, and blue horizontal and vertical traces on a viewing screen; a toroid deflection yoke associated with said color cathode ray tube and including a core of magnetic material having horizontal and vertical axes with horizontal and vertical deflection windings wrapped about said core and substantially asymmetrical about said horizontal axis and symmetrical about said vertical axis; and dynamic convergence means associated with said color cathode ray tube for effecting electron beam radial movement and in combination with said toroid deflection yoke effecting convergence of both horizontal and vertical red, green, and blue traces on said viewing screen.
 2. The deflection system of claim 1 wherein said deflection yoke includes first and second horizontal deflection windings disposed on opposite sides of said vertical axis wherein each have substantially the same number of turns.
 3. The deflection system of claim 1 wherein said deflection yoke includes first and second vertical deflection windings disposed on opposite sides of said horizontal axis with each having substantially the same number of turns.
 4. The deflection system of claim 1 wherein said blue electron gun of said color cathode ray tube is disposed above and said red and green electron guns are disposed below the horizontal axis of said core of said deflection yoke and said vertical deflection windings are formed to provide a lower concentration of windings at the top central portion as compared with the winding concentration at the bottom central portioN of said deflection yoke.
 5. The deflection system of claim 1 wherein said blue electron gun of said color cathode ray tube is disposed above and said red and green electron guns are disposed below the horizontal axis of said core of said deflection yoke and said first and second horizontal deflection windings have a greater concentration of turns above and adjacent the horizontal axis H-H'' than below and adjacent the horizontal axis H-H''.
 6. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said horizontal deflection windings have a portion above the horizontal axis defined by a formula substantially as follows: Ha -2.0246 + 2.0161 theta -0.0076495 theta 2 +0.000064226 theta 3 -0.0000010819 theta 4 wherein theta is the angular deviation from the horizontal axis H-H'' within 3*.
 7. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said horizontal deflection windings have a portion below said horizontal axis defined by a formula substantially as follows: Hb -0,77343 + 1.69224 theta +0.0022040 theta 2 -0.000063614 theta 3 -0.0000010819 theta 4 wherein theta is the angular deviation from the horizontal axis H-H'' within about 3*.
 8. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said vertical deflection windings include a first vertical deflection winding disposed above said horizontal axis with substantially similar portions on opposite sides of said vertical axis and each portion is defined by a formula substantially as follows: Va -0.52324 + 1.0379 + 0.071690 phi 2 -0.0017331 phi 3 + 0.000011160 phi 4 wherein phi is the angular deviation from the vertical axis V-V'' within about 3*.
 9. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said vertical deflection windings include a second vertical deflection winding disposed below said horizontal axis with substantially similar portions on opposite sides of said vertical axis and each portion is defined by a formula substantially as follows: Vb -0.77343 + 1.6922 phi + 0.0022040 phi 2 -0.000063614 phi 3 -0.00000044608 phi 4 wherein phi is the angular deviation from the vertical axis V-V'' within about 3* .
 10. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said vertical deflection windings include a first vertical deflection winding disposed above said horizontal axis with substantially identical portions on opposite sides of said vertical axis and at least 70 percent of the total turns of one portion within a counter-clockwise angle of 45* as measured from the vertical axis.
 11. The deflection system of claim 1 wherein said blue electron gun is disposed above and said red and green electron guns of said color cathode ray tube are disposed below said horizontal axis of said core and said vertical deflection windings include a second vertical deflection winding disposed below said horizontal axis with substantially identical portions on opposite sides of said vErtical axis and at least 70 percent of the total turns of one portion within a counter-clockwise angle of about 45* as measured from the vertical axis.
 12. In a color television receiver, a deflection system comprising: color cathode ray tube means providing red, green, and blue horizontal and vertical traces on a viewing screen, said traces derived from electron beams emanating from triad-arrayed red, green, and blue electron guns; toroid deflection yoke means associated with said color cathode ray tube means for effecting horizontal and vertical deflection of said electron beams, said yoke means including a core of magnetic material having horizontal and vertical axes, first and second horizontal deflection windings wrapped about said core on opposite sides of said vertical axis with each winding asymmetrical to said horizontal axis and first and second vertical deflection windings wrapped about said core on opposite sides of said horizontal axis with each of said windings substantially symmetrical to said vertical axis and asymmetrical to said horizontal axis; static convergence means associated with said color cathode ray tube for effecting convergence of said electron beams at the center of said viewing screen, said means including red, green, and blue radial magnets and a blue lateral magnet; and dynamic convergence means associated with said color cathode ray tube for effecting radial movement of said electron beams during deflection thereof by said yoke means to provide converged horizontal and vertical red, green, and blue traces, said means including an electromagnet for effecting radial movement of each of said red, green, and blue electron beams.
 13. The deflection system of claim 12 wherein said color cathode ray tube includes a blue electron gun above and red and green electron guns below said horizontal axis of said core and said deflection yoke means provides a lower concentration of vertical windings at the center portion above said horizontal axis as compared with the concentration of windings at the center portion below said horizontal axis whereby convergence of horizontal and vertical red, green, and blue traces is effected.
 14. The deflection system of claim 12 wherein said blue electron gun is disposed above and said red and green electron guns are disposed below said horizontal axis of said core and said first vertical deflection winding disposed above said horizontal axis includes substantially similar winding turns on opposite sides of said vertical axis with at least 70 percent of the total turns of one of said winding portions included within an angle of 45* as measured counter-clockwise of said vertical axis.
 15. The deflection system of claim 12 wherein said first and second vertical deflection windings each include at least 70 percent of the total turns within an angle of 45* as measured from the vertical axis of said core. 